Present Characters:
Leonardo (Leo or Leon)
Raphael (Raph or Raphie)
Donatello (Donnie or Tello or Donald)
Michaelangelo (Mikey or Miguel)
Hizuki
Sky Summers
Cyber Jenny
Plum Rivers
April O'Neil
Splinter/Lou Jitsu

Future Characters:
Master Leonardo
Master Michaelangelo
Casey Jones Jr.
Kiko Hamato, Daughter of Leonardo and Hizuki
Amethyst Hamato, Daughter of Donatello and Cyber
Amora Hamato, Daughter of Raphael and Sky
Opal Hamato, Daughter of Michelangelo and Plum